Center for Molecular Imaging, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center, Houston, Texas 77030, USA.
Neurogastroenterol Motil. 2011 Sep;23(9):881-e344. doi: 10.1111/j.1365-2982.2011.01736.x. Epub 2011 May 31.
After intravenous (i.v.) administration, indocyanine green (ICG) is known to be secreted into bile from the liver via the biliary tracts, enabling fluorescent delineation of the intestine. In addition, ICG is a near-infrared (NIR) excitable fluorophore, capable of providing exogenous contrast for rapid NIR fluorescence imaging. We sought to quantify the intestinal motility using dynamic NIR fluorescence imaging after injection of ICG.
C57BL6 mice were dynamically imaged immediately before and up to 24h after i.v. and intradermal (i.d.) injection of 50 and 10μL of ICG, respectively. Necropsy was also performed 1h postinjection and the entire gastrointestinal tract was isolated and exposed for ex vivo fluorescence imaging.
The secretion of ICG-laden fluorescent bile into the duodenum was observed in vivo and confirmed in situ. Different patterns of the intestinal motility, such as peristaltic and segmental motions, were dynamically imaged in vivo. Our imaging data showed that the frequency of contractions ranged from 27 to 35cyclesmin(-1) and the propagation velocity of peristaltic waves ranged from 0.82±0.5 to 2.04±1.12cms(-1) .
CONCLUSIONS & INFERENCES: Dynamic NIR fluorescence imaging with injection of ICG can provide a method for diagnostic motility testing for intestinal motility disorders or dysfunction and for potential evaluation of therapeutic agents.
静脉注射（i.v.）后，已知吲哚菁绿（ICG）通过胆管从肝脏分泌到胆汁中，从而能够荧光描绘肠道。此外，ICG 是一种近红外（NIR）可激发荧光团，能够为快速 NIR 荧光成像提供外源性对比。我们试图通过注射 ICG 后的动态近红外荧光成像来定量肠道蠕动。
在 i.v. 和皮内（i.d.）注射 50 和 10μL 的 ICG 之前和之后，立即对 C57BL6 小鼠进行动态成像，分别持续至 24 小时。注射后 1 小时还进行了尸检，并分离出整个胃肠道进行离体荧光成像。
在体内观察到载有 ICG 的荧光胆汁排入十二指肠，并在原位得到证实。在体内动态成像不同的肠道蠕动模式，如蠕动和节段性运动。我们的成像数据显示，收缩频率范围为 27 至 35 个循环 min(-1)，蠕动波的传播速度范围为 0.82±0.5 至 2.04±1.12cms(-1)。
注射 ICG 的动态近红外荧光成像可以为肠道运动障碍或功能障碍的诊断性运动测试提供一种方法，并可能评估治疗剂。
